LEXINGTON, Mass. and LONDON, Dec. 07, 2017 — Nightstar Therapeutics plc (NASDAQ:NITE), a clinical-stage gene therapy company developing treatments for rare inherited retinal diseases, today announced that the company will participate in a fireside chat at the BMO Capital Markets Prescriptions for Success Healthcare Conference on Thursday, Dec. 14, 2017 at 9:00 a.m. ET in New York City.To access the live webcast, please visit ir.nightstartx.com. A replay of the webcast will be available on the Nightstar website for 60 days following the conference.About NightstarNightstar is a leading clinical-stage gene therapy company focused on developing and commercializing novel one-time treatments for patients suffering from rare inherited retinal diseases that would otherwise progress to blindness. Nightstar’s lead product candidate, NSR-REP1, is being developed as a treatment for patients with choroideremia, a rare, degenerative, genetic retinal disorder that has no current treatments and affects approximately one in every 50,000 people. Positive results from a Phase 1/2 trial of NSR-REP1 were published in The Lancet in 2014 and in The New England Journal of Medicine in 2016. Nightstar plans to commence a Phase 3 registrational trial of NSR-REP1 for choroideremia at sites in the United States, Europe and Canada in the first half of 2018. Nightstar’s second product candidate, NSR-RPGR, is currently being evaluated in a Phase 1/2 clinical trial for the treatment of patients with X-linked retinitis pigmentosa, an inherited X-linked recessive retinal disease that affects approximately one in every 40,000 people.For more information about Nightstar or its clinical trials, please visit www.nightstartx.com.Forward-Looking StatementsThis press release contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, including, but not limited to: statements about our plans to develop and commercialize our product candidates, our planned clinical trials for NSR-REP1 and NSR-RPGR, the clinical utility of our product candidates, the prevalence of patient populations for our targeted indications, and the utility of prior preclinical and clinical data in determining future clinical results . These forward-looking statements are based on management's current expectations of future events and are subject to a number of involve substantial known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from the information expressed or implied by these forward-looking statements, including the risks and uncertainties set forth in the “Risk Factors” section of our prospectus filed pursuant to Rule 424(b)(4) under the U.S. Securities Act of 1933, as amended, on September 28, 2017, and subsequent reports that we file with the U.S. Securities and Exchange Commission. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. The forward-looking statements in this press release represent our views as of the date hereof. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law. You should, therefore, not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this press release.Contact:Senthil Sundaram, Chief Financial Officer[email protected]Alicia Davis, THRUST IR910-620-3302[email protected]